Group 2 Flashcards
What are group 2 elements sometimes called?
Alkaline-earth metals
Why are group 2 elements sometimes called alkaline-earth metals?
Due to the alkaline properties of the metal hydroxides that they form
Are group 2 elements reactive metals?
Yes
Do group 2 elements occur in their elemental form naturally?
No
How are group 2 hydroxides formed?
Through the reaction of a metal oxide and water
Give an equation of the reaction between strontium and water with state symbols
SrO (s) + H2O (l) → Sr(OH)2 (aq)
What are the group 2 hydroxides only slightly soluble in?
Water
What is released when the group 2 hydroxides dissolve and dissociate?
Metal cation
Hydroxide OH- ions
Write an equation for the dissociation of calcium hydroxide with state symbols
Ca(OH)2 (s) + aq → Ca2+ (aq) + 2OH- (aq)
Why does the solubility of the hydroxide increase down the group?
More OH- ions present in the solution
Meaning it is more alkali
What is the pH range of the hydroxide solutions?
pH 8 to pH 14
What is the use and reason of Ca(OH)2?
Agriculture
Neutralises acidic soils
What is the use and reason of Mg(OH)2/CaCO3?
Treating indigestion
Neutralises excess stomach acid (HCl)
What is the use of BaSO4?
Diagnostic medicine
What is the use of CaCO3?
Constructions and sculptures
Why do group 2 metals have high melting and boiling points?
They have strong metallic bonds in their giant metallic lattice structures
Why can group 2 metals conduct electricity?
Due to the delocalised electron that are mobile
Why are group 2 metals considered s-block elements?
Because the highest energy electron is found in an s subshell/orbital
Why do group 2 atoms act as reducing agents?
They lose 2 electrons from their outer shell
Meaning they undergo oxidation
State and explain if the second ionisation energy for strontium was greater, smaller or the same as the first ionisation energy
Will be greater
The proton to electron ratio has increased
Ionic radius has reduced
Harder to remove an electron from an ion than an atom
Why are all of the group II metals are stored under liquid paraffin oil?
Prevent reaction with oxygen in the air
How can the oxidation be seen with a freshly cut piece of calcium?
When left in the atmosphere it quickly becomes discoloured
Write an equation for to show the oxidation of calcium by oxygen to form one basic product, include state symbols
2Ca (s) + O2 (g) → 2CaO (s)
What would be observed when a group 2 metal reacts with water?
Fizzing
Solid dissolving
Colourless solution being formed
